Hydraulic-ram control



W. W. MACDONALD. HYDRAULIC RAM CONTROL. APPLICATION FILED SEPT-3,1919.

Patented Oct. 25, 1921.v

I N ENTO R 745144 Mafia/mid A r'roaunxs W. W. MACDONALD.

HYDRAULIC RAM CONTROL.

APPLICATION FILED SEPT-3.1919.

Patented Oct. 25, 1921.

A'r'ro RNEYS 3 SHEETSSHEET 2- INTENTOR WWI/46202261102 W. W. MACDONALD. HYDRAULIC RAM CONTROL. APPLICATION FILED SEPT-3,1919.

Patented Oct. 25, 1921.

3 SHEETS-SHEET 3.

m h w m W W &

.MNM

UNITED STATES PJEENT OFFICE.

WILLIAM W. MAcDONAL-D, OF SAN FRANCISCO, CALIFORNIA.

HYDRAULIC-RAM CONTROL.

- Application filed September 3, 1919. Serial No. 321,493.

draulic-Ram Controls, of which the following is a specification.

This invention relates to a hydraulic ram and particularly to a means whereby a liquid under pressure may be delivered to the ram and to a valve whereby the flow of liquid is regulated.

One of the objects of the present inventionis to provide a hydraulic ram control to be employed in conjunction with the steering gear of an automobile, the rudder mechanism of a ship or similar installations. Further, to provide a mechanism of the character described, which is simple and substantial in construction, responsive, sensitive and quick in action, and in which back lash or lost movement is entirely eliminated.

Another object of the invention is to pro- I vide a hydraulic ram from which movement mav be transmitted to asteering mechanism and in conjunctiontherewith a constantly operated pump," whereby a liquid under pressure may be delivered to hydraulically move the ram in one direction or another.

Another object of the invention is to provide a controlling valve whereby the liquid supplied may be circulated through the pump or delivered under pressure to one end or another of the ram; further, a valve by which the liquid delivered to the ram may be trapped or locked so as to prevent back lash or play in the ram.

Another object of the invention is to provide means for hydraulically balancing the controlling valve to reduce wearv therein to a minimum.

Further objects will hereinafter appear.

The invention consists of the parts and the construction, combination and arrangement of parts as hereinafter more fully described andclaimed, having reference to the accompanying drawings, in which Figure 1 is a plan viewof a front end of an automobile, showing the application of the invention to the steering mechanism on the automobile.

Fig. 2 is an end view of the controlling valve.

Fig. 3 is a. central, vertical section through the same.

Fig. 4 is a cross section of F i on line 4-4. g 3, taken F g. 5 is a section similar to Fig. 4, taken on l1ne 5-5 of Fig. 3. v i

Fig. 6 is a detailed view of the over-runnmg clutch.

Fig. 7 is a diagrammatic view of the pump, regulating valve and the ram, showing the pipe connections through which the l1 u1d employed is circulated.

Specification of Letters Patent. Pate t d O t 25 1921 eferring to the drawings in detail, A

indicates the main frame of an automobile; 2, the front wheels 3, the shaft supporting the same; 4:, the steering knuckles; 5, the t1e rod connecting the same; and 6, a link which 1s connected'at one end with a hydraulic ram generally indicated at B, and

at the opposite end with the steering knuckle. The automobile is otherwise provided with a suitable form of motor C, from which power is transmitted in the usual manner by means of a propeller shaft 7 to the rear driving wheels not here shown.

Suitably supported with relation to the main frame A is a standard form of rotary pump I), through which extends a driving shaft 8, power being transmitted to rotate said shaft by means of two separate driving connections shown at 9 and 10. Both drives consist of sprocket gears and chains, as

shown, one drive being transmitted to shaft 8 from the propeller shaft 7 as indicated at 9, and one drive being transmitted direct from the engine crank shaft 11 to the pump shaft 8 by means of the sprocket chain 10, the sprocket gears secured on the pump shaft 8 being each provided with an over-running r ratchet clutch of the type shown in Fig. 6. The purpose of providing two independent drivin connections. is to insure constant operatlon of the rotary pump D whether the automobile is coasting down hill or being driven by engine power. For instance, if coasting down hill it is obvious that the propeller shaft 7 will rotate while the engine crank shaft will stand still. Power will therefore be transmitted through the driving connection 9 and thereby maintain the pump in operation. Again, if the car is proceeding under engine power, it is possible that,

the speed of the engine crank shaft will exceed that of the propeller shaft. Power will then be transmitted through the driving conliquid deliver-ed is diagrammatically illus-' motion 10 direct to the pump shaft. In

'trated'in Fig. 7 in, which D indicates the rotary pump, B, the ram, and E, the regulating valve. The ram consists of a cylinder 12, through which-extends a piston rod 13,

said piston rod being supported in bearings 14,-disposed at-opposite ends of the cylinder and are further provided with stufiing boxes 15 to reduce leakage 'to a minimum.

S'ecured on the piston rod within the cylinder is a piston or ram 16, and formed in the cylinder are a pair of ports 17 and 18,

one being disposed at each end of the. c linder. These orts alternately serve the unc tion of supp y and discharge ports and arein this instance connected with a regulating valve E by means of a pair of pipes 19 and 20. The pump D is provided with a discharge port 21 and a return port 22, the discharge port being connected with the regulating valve by means of a pipe 23 and the return port by-means of a pipe 24. Connected with the pipe 24 by meansof a pipe 25 is" a liquid supplying tank 6 and interposed between the tank '26 an thefpipe 24 1s a check valve 27, the function of which" will hereinafter be described.

The regulating valve consists of a "casing,

28 in' which is formed four ports such as indicated at 29, 30, 31 and 32,"the port 29 being connected with a pipe 20, the port 30 to the pipe 19, the ort 31 with a pipe 23, and the port 32' wit .a .pipe 24. Mounted interior of the casing 28 is a disk valve 33 in which is formed a pair of ports 34 and 35. Forming a closure for the casing 28 is a head plate36, in which is formed a studing box 37. Extending through'the stufling ts 33' is .secured. Secured on the outer end of box is a shaft 38 upon which'tliedisk valve the shaft 38 is a crank arm 39 and suitably supported with relation to the main frame A is'a steering wheel 40'which isprovided i For the purpose of hydraulically ba ing the disk valve 33 and-also-for the purforthe purpose of transmitting a turning movementto the shaft 38 by means of a crankarm 41 and a link.42 (see Fig. 1;.

anc-

pose of permitting a free circulation through the rotar pump D, I provide an annular port 43 see Figs. 3 and 4). This port is formed inthe head plate 36 and functions in the following manner If the disk valve assumes the dotted line position shown in Fig.7, it is obvious that oil or other liquids circulated by the pump D will discharge through pipe23 and enter the controlling valve E through port 31; The liquid will ,uid supplied by ump .D under pressure, to

the cylinder of t e ram for-the purpose of moving the piston inthe direction of arrow on, it is only necessary to turn the disk valve until the port 34 registers with the ports 29 and 31 and port 35 registers with ports 30 and 32. Liquid discharged by the pump D will, then flow through pipe 23 and enter the controlling valve by means of port 31. It will then pass through the I ort 34 in the disk valve and will there ore discharge through port 29 and enter the cylinder of the ram by means of pipe 20. Simultaneously, oil will discharge from the opposite end of the ram cylinder through pipe 19, as

the suction side of the pump will draw the oil from said end of the ram cylinder, due to the fact that the return pipe 24 communicates with pipe 19, -by means. of.the communicating passage formed by port 35 as this registers with. ports 30 and 32.

If it-is desired ,to'deliver liquid under pressure to move the piston 16 in a direction op osit efto that indicated by arrow a, it is on y necessary to move the disk valve. into position where port- 34 will. register .withports 30 and 31 and where port 35 will register with rts 29 and 32; The liquid under pressure ischargin thus enter pipe 19 by way of ports 31, 34 and 30 and liquid will simultaneously be returned to the pump by the suction or return pipe 24'as port 35 registers with ports29 and32..- i

From the foregoing description it can be seen that liquid under pressure may be constantly circulated through the pum D and the controlling valve E or it may e delivered under ressure to either end of the ram cylinder. moved from either .end of the ram cylinder and returned to the suction side of the pump.

through pipe 23 will iinilarly, that liquid-may be re- By providing the supply tank 26, shown in Figs. 1 and 7, it is possible to automatically re-supply any liqui which might be lostb leakage. This is dueto the fact th e tank is connected with the suction side of the pump and by providing a check valve, as

valve, subject to comparatively little wear and leakage has been provided, as it is hydraulically balanced by means of the port formation shown at 43. Fourth, by providing a tank such as indicated at 26, it is possible to automatically re-supply any liquid which may be lost by leakage or otherwise. Fifth, by providing a controlling valve as here shown, it is possible to trap all the liquid in the cylinder ofthe hydraulic ram so as to prevent either admission or discharge of the liquid and as the liquid is non-compressible, it is obvious that back lash or play is positively prevented. Sixth, by providlng over-running clutches such as shown in Fig. 6, it is possible to drive the pump when coasting down hill or it is possible to drive the pump directly from theengine, this being of importance as it is not absolutely necessary to depend upon the engine at all times for maintaining the pump in operation.

While the ram, pump and controlling valve are here shown, it is employed for'the .purpose of operating the steering mechanism of an automobile; I wish it understood that it might be equally applicable for connection with the rudder mechanism of a ship and for other purposes. Similarly, while a more or less specific design and arrangement is here shown, I wish it understood that such features may be varied Within the scope of the appended claims, without departing from the spirit of the present invention.

By referring to Fig. 7 i it willbe seen that I have placed a by-pass pipe 40 between the return pipe 24 and the tank 26; further, that a pressure-reducing valve ll is mounted in sald connection. The function of this valve is important as it prevents building up of excess pressure in the lines. For instance,

take place on the discharge side until 1200 pounds is, obtained and thus pressure will finally be transmitted to the return side, thus increasing the return side pressure from 800 to 1200 pounds. In actual practice I find that the pressure gradually builds up but that the valve 41 will automatically maintain the pressure 'at any point desired so if the valve is set for a pressure of 100 pounds and oil is delivered to pipe 24 at a higher pressure then sufficient oil will bypass-through the valve to reduce the pressure to 100 and thereby prevent building up of excess pressures.

Having thus described my invention,Wha I claim and desire tosecure by Letters Patcut is l. The combination with the cylinder of a hydraulic ram, of a piston reciprocally mounted in the cylinder dividing'the cylinder into two chambers, a continuously operated pump adapted to maintain a body of liquid in constant circulation, a valve casing interposed between the pump and the cylinder of the hydraulic ram, a pair of ports formed in said casing, one communieating with the discharge side of the pump, and one communicating with the suction side of. the pump, a second pair of ports formed in the casing, one communicatin with one end of the ram cylinder and the other with the opposite end of the ram cyl inder, a valve turnably mounted within the casing adaptedfto form communication between the discharge and. the suction side of the pump to permit a continuous circulation of the liquid through the pump and the valve, said valve also adapted to be turned soas to form communication between the discharge side of the pump and either end of the cylinder and between the suction side of the pump and either end of the cylinder, means permitting the building up of pressure on the discharge side ofthe pump, and means interposed between the valve and the pump for automatically unloading saidpressure.

2. The combination with the cylinder of a hydraulic ram, of a piston reciprocally mounted in the cylinder dividing the cylinder into two chambers, a continuously operated pump adapted to maintain a body of liquid in constant circulation, a valve casing interposed between the pum and the cylinder of a hydraulic ram, a pair of ports formed in said casing, one communicating with the discharge side. of the pump, and one communicating with the suction side of the pump, a second pair of ports formed in the casing, one communicating with one end of the ram cylinder and the other with the opposite end of the ram cylinder, a valve turnably mounted within the casing adapted to form communication between the discharge and the suction side of the pump to permit a continuous circulation of the liquid jthrough the pump and the valve, said valve also adapted to be turned so as to form communication between the discharge side of the pump and either end of the cylinder and between the suction side of the pump and either end of the cylinder, means permitting the building up ofpressure on the discharge side' of the pump, a source of liquid supply connected with the suction side of the pump and interposed between the of liquid in constant circulation,-a control ling valve interposedv between the cylmder of the ram and the pump adapted to norvalve and the pump, an unloading valve interposed between the suction side of the pump andfthe source of liquid su ply, said valve automatically unloadin t e maximum pressure built up on the lscharge side of the pump.

'3. The combination with the cylinder of a hydraulic ram, of a piston reciprocally mounted in the cylinder and dividing the cylinder into two chambers, a constantly o crating pump adapted to maintain a be 'mally maintain a' circulation of liquid through, the ump and valve, and also adapted to dehver li uid under pressure to either end of the ray inder and simultanes an unloading device interpose -85 either end of the cylinder to t e meanspermittingthe building up 0 presously adapted to retu'rnthe 1i uid from p,

sure in the liquid delivered by the ump and between thevalve andthe suction side of the pump adapted to be adjusted to unload the maximum pressure produced on the discharge side of the pump and also adapted to main- Ltain a predetermined pressure on the suction and discharge-side of the pump,

4, Thecombination with a cylinder of a a hydraulic ram, of a piston reciprocally, mounted in the cylinder and dividing thecylinders into two separate chambers, a source of liquid supply, means for maintain- -ing said liquid-in circulation and for provalve adapted to deliver the liqui under. pressure to either end of the cylinder and 0 duclng "a pressure thereon, a re lating adapted tosimultaneously returnthe liquid either end of the cylinder, and means interposed between the valve and the suction I side ofthe pump for maintaining'a predethereto,

escrr ed culation and .adapted to im art pressure aprime mover-to whlch the liquid 7 under pressure is adapted to be delivered for operation thereof, a controlling valve interposedbetween the'pump and the prime draulically mover, said valve adapted to maintain a .circulationof liquid through the pump and valve, and also adapted to deliver the liquid under pressure to the prime mover andsimultaneously. adapted to return the liquid to the pump, a source of liquid supply connected with thesuction side of the. pump only and an unloadin valve interposed between the valve and t e suction side of the pump and adapted to discharge into the source of liquid supply to unload the pressures built up by the pump during operavalve also adapted .to maintain a predetermined pressure both on the suctionand discharge side of the pump.

6. The combination with a continuously 'tion of the prime mover, said unloading operating rotary pump and a ram cylinder, v

'of a piston reci rocally. mounted in the .cylinder and divi mg the cylinder into two separate chambers, a controlling valve interposed between the. pump and the cylinder, said valve comprislng a casing having a pair of ports formed therein, one adapted to communicate with a discharge side of. the

pump and one with the suction side of the pump, a second pair of ports formed in the casing, one communicatingwith one end of the cylinder and one with the opposite end of the 7 cylinder, a disk valve within the casing, a pair of ports formed in said disk valve, a head plate for the casing inclosing the disk valve, and an annular port formed in the head .plate to hydraulically balance the disk valve.

37. The combination with a continuously operating lj'otary pump and a ram cylinder,

of a. plston 1 reciprocally mounted in the cylinder and dividing the cylinder into two separate chambers,- a controlling valve interposed between the pump and the cylinder, said valve comprising. a casing having a pair of ports formed therein, one adapted to communicate with a dischargeside of the pump and one with the suction side of the pump, asecond pair 0 f ports formed in the casing, one-communicatmg with one end of the cylinder and one with the opposite end of the cylinder, a disk I valve within the casing, a formed in said disk valve, a ead plate for the casing inclosin the disk valve, an annular port formed in the head plate to hy-- balance the disk valve,-and means 3 for turning the disk valve.

8. The combination with a continuously operating rotary pump and aram cylinder,

'-'of' a piston reciprocally mounted in the" cylinderand dividing the c linder into two separate" chambers, a contro ling valve interposed between the pump and the cylinder,

said valve comprising a casing havinga air o'f ports formed therein, one adapted to communicate with a dischar' 7 pump and one with the suction side .of the side of the pair. of port; 115

pump, a second pair ofports formed in the casingi one communicating with one end of head plate to hydraulically balance the disk V of the pump respectively, t e

valve, means for'turning the disk valve, and a liquid supplying tank connected with the suction side of the pump, and a check valve interposed between the supply tank and the suction side of the pump to permit .flow from the liquid supplying tank to the suction side in onedirection only.

9. The combination with the cylinder of a hydraulic ram, of a piston reciprocally mounted in the cylinden dividing the cylinder into two chambers, a continuously operated pump adapted to maintain a body of liquid in constant circulation, a valve through which said liquid is adapted to be circulated, a pair of pipes'connecting the valve with the suction and discharge sides of the pump respectively, a second air of pipes connected with the valve an with opposite ends of the ram cylinder, a su ply tank connected with the suction pipe .0 thepump, a by-pass pipe connected with the suction pipe and the supply tank, and a pressure reducing valve in the by-pass connection.

10. The combination with the cylinder of a hydraulic ram, of a piston reciprocally mounted in the cylinder dividing the cylinder into two chambers, a continuously operated pump adapted to maintain a body of liquid in constant circulation, a valve through which said liquid is adapted to be circulated, a pair of pipes connecting the valve with the suction and discharge sides a secondpair of pipes connected with opposite ends of the ram cylinder, a su ply tank connected with the suction ipe oi the pump, a by-pass pipe connect with the suction pipe and the sup 1y tank, a pressure reducin valve in the g and a c eck valve inte sed between the supply tank and the suction pipe.

valve and with y-pass connection,

11. The combination with the cylinder of a hydraulic ram, o'f a piston reciprocally mounted in the cylinder dividing the cylinder into two chambers, a continuously operated ump adapted to maintain a body of liqui in constant circulation, a valve through which said liquid is adapted to be circulated, means connecting the valve with the suction and discharge sides of the pump respectively, other means connecting the valve with the opposite ends of the ram cylinder, an automatic priming tank connected with the suction side of the pump and in constant communication therewith, and means also connected with the suction side of the pump and interposed between the valve and the suction side of the ump for automatically preventing the buildmg up of pressures beyond predetermined limits on the suction side of the pump when the valve is turned to a position where it permits continuous circulation of liquid through the valve and the ump. v

12. The com ination with a double ended ram and a pump for delivering liquid under pressure thereto, of a valve interposed between the ram and the pump, said valve adapted to form a circulating connection between the discharge and the suction side of the pump, and also adapted to direct the liquid under pressure to either end of the I ram and to return the liquid to the suction of the pump from either end of the ram, an automatic priming tank interposed between the .valve and the pump and in constant communication with the suction side of the ump, and other automatic actuated-means mterposed between the valve and the pump and connected with the suction side of the pump to prevent buildin up of pressures on the suction side beyonc l a predetermined pressure.

In testimony whereof have hereunto set my hand in the presence of two subscribing wltnesses.

. WILLIAM w. MACDONALD.

Witnesses WM. H. BAUER, A. W. Hmm. 

